Problem with Codeigniter

Codeiginter session Library is internally using COOKIE, so you may get cache issue mostly in IE browsers, means cookie is store in client browser, when client received response header then updated session value will show on client end.

What do you mean? What's cached?

i am specially saying for IE browser, I had faced strange issue with CI cart item update on IE browser, the cart items was not being update on page load, when i reload page by "ctrl+f5" then cart items was updating.

I google issue, and found IE browser cached response header, see these links
https://msdn.microsoft.com/en-us/library/bb250442.aspx
https://support.microsoft.com/en-us/kb/234067/en-us
The issue resolved when i added cache control header in repose.

PHP Code:

  $this->output->set_header("Cache-Control: no-store, no-cache, must-revalidate, no-transform, max-age=0, post-check=0, pre-check=0");
  $this->output->set_header("Pragma: no-cache"); 


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